A reduced salivary secretion arises or develops with increasing age. Thus, most elderly people have problems with a dry mouth. Some general diseases also give rise to a reduced secretion of saliva, so called hyposalivation. The most prominent one thereof is Sjoegren's syndrom. Furthermore, several generally used medicins, inter alia antihypertensives, antiulcer agents and antipsychotics, cause such a hyposalivation. In other words dryness of the mouth, or xerostomia, is a common disease that affects a large number of the population transiently or permanently.
The reduced secretion of saliva causes subjective symptoms in the form of burning tongue, mouth, pharynx and esophagus and sensitivity to spicy food and beverages. Some individuals are also affected as to speech and swallowing. Objectively dryness of the mouth often causes caries and periodontitis, which are difficult to treat since the reduced secretion of saliva results in a more pronounced retention of bacteria in the oral cavity and on the teeth. The resistance of the mucosa against colonization of bacteria is reduced and especially fungal infections are common in connection with individuals with xerostomia. Furthermore, people carrying so called plate prosthesis often have great problems with the retention of the prosthesis as well as infection of the mucosa as consequences of the dryness of the mouth.
There are agents against xerostomia on the market, but these are very varying as to efficiencies. Serious shortcomings in connection with the agents on the market are inter alia short and minor effects and in some cases a disagreeable taste results. Moreover, in general the prices are high which means an economic drawback for persons which have to utilize such agents continuously.
The salivary glands of the mouth normally produce around 1-1.5 1 of saliva per 24 hours, and it must be considered unrealistic to utilize a saliva substitute which has to be taken in such a volume per 24 hours. Therefore, said agent has to possess such retention properties that it is retained and lubricates the teeth and mucosas for a relatively long time after a dosage has been taken. Furthermore, the preparation has to be swallowable so as to reduce the problems or symptoms in the pharynx and the esophagus.
According to the present invention novel saliva substitutes are provided which eliminate or at least significantly reduce the disadvantages of the previously known agents and which fulfil the requirements for agents of this type.